Recent management concepts in the management of Atrophic rhinitis and empty nose syndrome

Introduction:

The presence of normal sized nasal turbinates covered by normal moist mucosa is vital for the normal function of the nose.  It should also be remembered that the receptors for initiating nasobronchial / nasal cardiac reflexes are found embedded in the mucosal lining of the nasal turbinates.  Surgical augmentation of atrophied turbinates and nasal mucosa will help in the restoration of nasal function and regeneration of nasal mucosa.  Usually various types of implant materials are considered for this purpose.

Commonly used implant materials:

1. Bone
2. Cartilage
3. skin
4. Fat
5. Plastic
6. Calcium hydroxyapatite


Role of Hyaluronic acid as an implant:

Hyaluronic acid is a naturally found polysaccharide consisting of a linear chain of fragments of D-glucoronic acid and N-acetlyglucosamine that alternate in the structure.  In its pure form it is not an allerge and does not stimulate immunogenic rejection process.  In view of its negative struture it absorbs large quantities of water.  On absorption of water hyaluronic acid forms a gel like structure.  It is extensively being used in plastic and reconstructive surgical procedures.  Its important unique property is that it maintains its liquid form when it is under pressure, the moment the pressure reduces it solidifies.  Hence it can be injected through a small needle.    It has another important property i.e. Isovolumetric degradation, which indicates single molecules of this substance undergoes periodic degradation while the remaining molecules absorb large amounts of water thereby enabling it to maintain its volume.  The overall volume of the gel maintains a constancy.



Hyaluronic acid can be injected submucosally thereby enlarging the size of the turbinates.  It can also be injected under the septal mucosa.  This not only cause narrowing of the nasal cavity but also promotes regeneration of nasal mucosal lining.  If a cannula is used to inject hyaluronic acid instead of needle it causes less mucosal trauma thereby minimizing the risk of accidental intravascular injection.  It would be better if the quantity of hyaluronic acid injected is the same on both sides.  Studies conducted by Marek Modrzynski, M.D.
 showed promising results.

Parapharyngeal tumor removal using Mandibular swing approach a digital atlas

Preauricular sinus compete excision is the only way out.

Preauricular sinus is an embryological aberration involving the developing pinna.

Theories of preauricular sinus formation:

Embryological fusion theory:

This commonly accepted theory suggests the preauricular sinus develops due to fusion defects involving the 6 hillocks which develop into the future pinna.

Ectodermal infolding theory:

This theory attributes preauricular sinus to ectodermal infolding defects that occur during development of pinna. Ofcourse this theory has no takers. This theory assumes that preauricular sinus forms part of other branchogenic malformations.

Various syndromes associated with preauricular sinus formation are:

1. Branchio oto renal syndrome
2. Branchio oto urethral sundrome
3. Branchio otic syndrome
4. Branchio oto costal syndrome
5. Cat eye syndrome
6. Trisomy 22

Surgical options for management of preauricular sinus:

Jensma technique is commonly preferred surgical treatment modality. In this technique the tract is identified after injecting dye (GV paint) via the punctum. A circular incision is made to encircle the opening of the preauricular sinus and the whole sinus is followed using dye diffusion as a guide. Major problem of this technique is that the recurrence rate is very high. It is not a suitable approach in patients with infected preauricular sinus.

Common causes of recurrence:

1. Incomplete removal of lesion
2. Failure to use magnification during surgery
3. Skill of the surgeon

Supra auricular approach:

This is a more radical approach. Major benefit of this procedure is it low recurrence rate. This surgery is performed using a comet incision. The head of the comet incision is around the external opening of the sinus. The tail of the comet is fashioned in such a way that it passes anterior to the helix, superior to the pinna over the temporal area. The temporalis fascia is the medial limit of the dissection. All the tissue superficial to the temporalis fascia should be removed. It is also important to remove a cuff of cartilage around the outer opening of the preauricular sinus.

Picture showing preauricular sinus

Comet incision shown

Removal of sinus along with a bit of helical cartilage

View of wound closure

You can view the procedure below;

Pleomorphic adenoma parotid gland

Clinical details:

13 years old boy came with complaints of:

Swelling over left side of cheek - 3 years duration
Swelling showed progressive increase in size

The swelling was non tender, not associated with febrile illness.

FNAC report:

Fine needle aspiration cytology from the mass was reported as pleomorphic adenoma.

Surgery:

Since this is a surgical problem the patient was taken up for surgery under general anesthesia.

Discussion:

Pleomorphic adenoma is the commonest benign tumor involving the salivary glands. This is characterised by proliferation of glandular cells along with myoepithelial components. This tumor has a tendency for malignant transformation.

Histologically this tumor is highly variable and variations are evident even within individual tumors.
Classically these tumors show biphasic manifestation with admixture of varying amounts of polygonal salivary gland cells and spindle shaped myoepithelial cells. The underlying stroma could be mucoid / myxoid / cartilagenous / hyaline. Even though these tumors are not encapsulated but thickening of parotid fascia around the mass gives it an encapsulated appearance (pseudocapsule).

The main cause for this tumor is juxtapositioning of PLAG gene to the gene for beta catenin. This causes activation of catenin pathway leading on to inappropriate cell division.

An interesting case of metallic foreign body (Nail) right orbit being removed

Case report:
13 years old male patient came to the OPD with h/o injury just below right eye.  When he came the injury was 4 days of duration.  He had undergone wound suturing as soon as he sustained the injury.

On examination:
Proptosis (mild) of right eye+
Sutured wound seen just below right orbit.  wound had healed.
Upwards movement of eye was restricted.
Lateral movements of the eye was normal

Imaging:

Plain x-ray skull lateral view was taken immediately.

It showed the presence of metallic foreign body


CT scan showed:

Metallic foreign body in the floor of right orbit with evidence of # of orbital floor

Patient was taken up for surgery under general anesthesia.  The metallic foreign body was removed via right infraorbital incision.  This was preferred because he already had the sutured scar in that area.

Surgical video clipping:




Discussion:

This case is presented for its rarity.  Without proper history it is very difficult to diagnose orbital foreign bodies inside the orbit.  Retained foreign bodies in the orbit can cause:

1. Orbital hematoma
2. Orbital cellulitis
3. Ocular dysmotility
4. Proptosis
5. Orbital abscess
6. Blindness

Olfactory groove meningioma

Introduction:

Meningiomas are benign and rather slow growing tumor arising from arachnoidal cap cells. Statistically speaking meningiomas constitute about 20% of all primary intracranial tumors. Out of these 20% olfactory groove meningiomas constitute 10%. It was the Italian surgeon Francesco Durante who first reported the first successful resection of olfactory groove meningioma in 1885. In 1938 Cushing reported the largest series of olfactory groove meningioma which were resected via frontal craniotomy / subfrontal approach. It is really worthwhile to differentiate olfactory groove meningioma from other intracranial menigiomas as they differ in their presentation, symptomatology and management.

Sex ratio:

The female : male ratio is 2:1. Exact explanation for this variation is not available.

Pathophysiology:

Meningiomas arise from meningothelial cap cells that are largely distributed through the arachnoid trabeculations. The greatest concentration of meningothelial cells are seen in the arachnoid villi lining the dural sinuses, cranial nerve foramina, middle cranial fossa and cribriform plate area. This accounts for the common location of meningiomas i.e. Over the convexity, along the skull base and along the falx. Meningiomas are usually attached to the dura and are well encapsulated. Blood supply to these tumors arise usually from the dura and the anterior and posterior ethmoidal arteries.

Histology:

Histologically these tumors show features of bening lesions. These lesions classically appear as whorls of arachnoid cells surrounding a central hyaline material that eventually calcifies. These calcified areas are known as Psammoma bodies. These cells are arranged in sheaths separated by connective tissue trabeculations.

Subtypes of meningiomas:

Meningotheliomas

Fibrous types

Transitional types – Psammamatous tumors

Secretory meningiomas – Secretes Vascular endothelial growth factor. These tumors are characterized by the presence of marked oedema. They may be papillary or rhabdoid variants. These tumors are usually considered to be malignant in nature.

WHO histological grading of meningiomas:

Grade I: This grade is usually benign and 90% of all meningiomas belong to this category. They also carry the best prognosis and a very low recurrence rate.

Grade II: Atypical meningiomas come under this category. About 5% of all meningiomas belong to this grade. Tumors belonging to this grade have a high recurrence rate (about 50%).

Grade III: This grade of meningioma is frankly malignant constituting about less than 3% of all meningiomas.

Molecular biology:

Majority of meningiomas are associated with one / more focal chromosomal deletions. Malignant versions of meningiomas involve multiple chromosomal aberrations. These multiple chromosomal abberations cause extreme instability to the genomic structure thereby increasing the risk of malignant transformation.

Deletion and inactivation of NF2 gene on chromosome 22 is the predominant feature in sporadic meningiomas.

Risk factors contributing to meningioma:

1. Exposure to ionizing radiation – Studies have demonstrated that survivors of atom bomb explosion showed increased incidence of meningioma
2. Role of Hormones – Histologically meningiomas present with oestrogen, progesterone and androgen receptors. This could explain the increased incidence of menigioma in females.
3. Head injuries have been shown to increase the incidence of meningiomas.

Location of olfactory groove meningioma:

These tumors are seen in the midline and arise over the cribriform plate and frontosphenoidal suture area. A majority of these tumors occupy the floor of anterior cranial fossa extending from crista galli up to the tuberculum sella. Extension to ethmoidal sinuses occur in about a third of these patients. There are obvious similarities existing between posteriorly extending olfactory groove meningiomas and tuberculum sellae meningiomas. These two masses can be differentiated by studying their relationship with that of the optic apparatus. Olfactory groove meningiomas have a tendency to push optic nerves and chiasma downwards and posteriorly as they grow, where as tuberculum sellae meningiomas push the optic nerves and chiasma upwards and superolaterally as they grow because of their subchiasmal position.

Blood supply of olfactory groove meningiomas:

These tumors are supplied by:

1. Anterior ethmoidal artery
2. Posterior ethmoidal artery
3. Anterior branches of middle meningeal artery
4. Meningeal branches of ophthalmic artery

Clinical features:

These tumors are very slow growing ones and they are seen in the silent area. Hence to become symptomatic they need to enlarge their size to a great extent. Usually these lesions are incidental findings during routine imaging.

MRI is the most preferred imaging modality as this would clearly show the origin of the tumor from dura. These lesions appear isointense / hypointense to gray matter of brain in T1 weighted images and isointense to hyperintense in T2 weighted images. When gadolinum is used as contrast these lesions demonstrate homogenous enhancement.

Majority of meningiomas show marginal dural thickening that tapers peripherally. This tapering is classically known as the dural tail which is the characteristic feature which is revealed in the images.

Management:

This entirely depends on the age and physical fitness of the patient. If the tumors are small and seen in elderly and ill patients then serial imaging and observations would do. In symptomatic cases irradiation can be resorted to,

Surgical resection is the best option. Removal of these lesions is similar to that of any other skull base tumor.

Surgical management:

Cushing was the first to describe surgical resection of the tumor via unilateral frontal craniotomy. Other approaches available include:

1. Bifrontal craniotomy
2. Subfrontal approach
3. Pterional approach
4. Endoscopic approach

Bifrontal craniotomy combined with subfrontal approach: This approach provides wide exposure for complete removal of tumor. In this approach it is easy to drill out the hyperostotic area in the cribriform plate area. In this approach optic nerves also can be deroofed if need be. Major disadvantage of this approach is the amount of brain retraction that is needed.

Unilateral frontal craniotomy with subfrontal approach: This approach has the advantage of sparing the opposite frontal lobe and superior saggital sinus. The disadvantages include:

Smaller exposure

Excessive brain retraction

Pterional approach:

This is a rather new approach. It is less invasive than frontal craniotomy approaches. It avoids CSF leaks because the frontal sinus is not damaged. The optic nerve can be localised and exposed before tumor manipulation. Major disadvantage of this approach is the lack of working space. The wole dissection process needs to be carried out within a narrow angle.

Endoscopic resection:

This procedure is performed binaurally with the endoscope introduced through one nose and the surgical instruments via the other.

This procedure involves:

1. Bilateral maxillary antrostomies
2. Complete ethmoidectomies
3. Sphenoidotomies
4. Frontal sinusotomy

Unilateral / bilateral nasal septal flaps are harvested first. This helps in covering the dural defect.These flaps are tucked into the nasopharynx well out of the way of surgical field.

Modified Lothrop procedureis performed. The frontal intersinus septum should be completely removed.

Controlling the bleeding to the mass is the top most priority. The anterior ethmoidal artery should be identified and ligated. Anterior ethmoidal arteries should be sought and ligated on both sides. Posterior ethmoidal arteries also should be drilled out and ligated. Image guidance is used to identigy the anterior and posterior extent of the mass. The anterior cut is usually made at the level of posterior wall of frontal sinus and continued along the fovea ethmoidalis using drills and kerrison punch. The posterior resection is made as posterior as possible. This is usually governed by the posterior extent of the mass. It can be as posterior as the planum of sphenoid.

Dura is incised exposing the entire olfactory groove meningioma. Dissection is completed using a combination of blunt dissection, debrider and CUSA. Tumors involving the medial wall of the orbit may be considered to be rather suboptimal for endoscopic resection. While performing the resection of the tumor care should be exercised to dissect it between the tumor and arachnoid plane. The defect in the skull base is repaired using abdominal fat, reinforced with fascia lata and tissue glue is used to fix them in place.

Advantages of endoscopic approach:

1. The main site of recurrence i.e. The floor of the anterior cranial fossa is completely resected / drilled out.
2. Allows two surgeons to operate simultaneously there by ensuring clear surgical field
3. Very useful from the cosmetic point of view.

Role of irradiation in the management of meningiomas:

1. RT is indicated only in patients with recurrent tumors following surgical resection
2. In patients with atypical / malignant meningiomas after surgical extirpation of the tumor

Role of stereotactic radio surgery:

The major advantage of this procedure is that the irradiation dose at the edge of the neoplasm is greatly reduced thereby sparing the normal adjacent tissues. This procedure can be safely used to treat even large volume tumors close to critical intracranial structures.

Targetted molecular therapy:

This type of therapy aims at blocking the various signals leading to unbridled proliferation of cells. These include:

1. Inhibitor of PDGFR – This is infact a key driver of cell proliferation in meningiomas. Drugs that block this can help in arresting the growth of meningiomas. Classic example of these drugs is Imatinib.
2. Inhibitors of angiogenesis factor – Sorafenib and Sunitinib are examples of drugs belonging to this group